Lung Ultrasound for Diagnosing Pneumothorax in the Critically Ill Neonate

Lung Ultrasound to Assess the Etiology of Persistent Pulmonary Hypertension of the Newborn (LUPPHYN Study): A Pilot Study

INTRODUCTION

Persistent pulmonary hypertension of the newborn (PPHN) is a neonatal syndrome associated with significant morbidity and mortality that is caused by the failure of postnatal drop in pulmonary vascular resistance. In extreme cases, patients may require extracorporeal membrane oxygenation therapy (ECMO). The aim of this study was to explore lung ultrasound (LUS) patterns in newborns with PPHN requiring ECMO.

PATIENTS AND METHODS

From January 2014 to January 2018, LUS was performed on patients with PPHN admitted for ECMO treatment. PPHN diagnosis was based on clinical and echocardiographic findings. LUS was performed before patients underwent ECMO cannulation. An underlying diagnosis was made taking into account the patient's complete medical history, excluding LUS information. A blinded physician, unaware of the patient's clinical condition, analyzed the stored ultrasound images. Results were then compared with chest x-ray (CXR) diagnoses.

RESULTS

Seventeen patients were recruited; 12 were male (70.6%). The median gestational age was 38.7 weeks, with 13 term newborns (76.5%). Twelve were cannulated for VA ECMO, with a median ECMO run of 111.2 h. Six patients (35%) survived. Patients with alveolar capillary dysplasia with misaligned pulmonary veins, fetal ductus arteriosus constriction, or sepsis had normal LUS patterns (A-lines with lung sliding). LUS showed a better sensitivity (88.9%) and specificity (85%) than CXR (55.6 and 77.5%, respectively) in identifying patients with nonparenchymal lung disease.

CONCLUSIONS

LUS can provide essential information to help diagnose the underlying cause of PPHN in an earlier and more effective way than CXR. LUS is suitable for routine utilization in the intensive care unit.

Diagnostic Bedside Ultrasound Program Development in Pediatric Critical Care Medicine: Results of a National Survey

OBJECTIVES

To assess current diagnostic bedside ultrasound program core element (training, credentialing, image storage, documentation, and quality assurance) implementation across pediatric critical care medicine divisions in the United States.

DESIGN

Cross-sectional questionnaire-based needs assessment survey.

SETTING

Pediatric critical care medicine divisions with an Accreditation Council of Graduate Medical Education-accredited fellowship.

RESPONDENTS

Divisional leaders in education and/or bedside ultrasound training.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Fifty-five of 67 pediatric critical care medicine divisions (82%) with an Accreditation Council of Graduate Medical Education-accredited fellowship provided responses. Overall, 63% of responding divisions (34/54) were clinically performing diagnostic bedside ultrasound studies with no difference between divisions with large versus small units. Diagnostic bedside ultrasound training is available for pediatric critical care medicine fellows within 67% of divisions (35/52) with no difference in availability between divisions with large versus small units. Other core elements were present in less than 25% of all divisions performing clinical studies, with a statistically significant increase in credentialing and documentation among divisions with large units (p = 0.048 and 0.01, respectively). All core elements were perceived to have not only high impact in program development but also high effort in implementation. Assuming that all structural elements could be effectively implemented within their division, 83% of respondents (43/52) agreed that diagnostic bedside ultrasound should be a core curricular component of fellowship education.

CONCLUSIONS

Diagnostic bedside ultrasound is increasingly prevalent in training and clinical use across the pediatric critical care medicine landscape despite frequently absent core programmatic infrastructural elements. These core elements are perceived as important to program development, regardless of division unit size. Shared standardized resources may assist in reducing the effort in core element implementation and allow us to measure important educational and clinical outcomes.

Review of bedside surgeon-performed ultrasound in pediatric patients

PURPOSE

Pediatric surgeon performed bedside ultrasound (PSPBUS) is a targeted examination that is diagnostic or therapeutic. The aim of this paper is to review literature involving PSPBUS.

METHODS

PSPBUS practices reviewed in this paper include central venous catheter placement, physiologic assessment (volume status and echocardiography), hypertrophic pyloric stenosis diagnosis, appendicitis diagnosis, the Focused Assessment with Sonography for Trauma (FAST), thoracic evaluation, and soft tissue infection evaluation.

RESULTS

There are no standards for the practice of PSPBUS.

CONCLUSIONS

As the role of the pediatric surgeon continues to evolve, PSPBUS will influence practice patterns, disease diagnosis, and patient management.

TYPE OF STUDY

Review Article.

LEVEL OF EVIDENCE

Level III.

Visual assessment versus computer-assisted gray scale analysis in the ultrasound evaluation of neonatal respiratory status

Background and aim

Lung ultrasound has been used to describe common respiratory diseases both by visual and computer-assisted gray scale analysis. In the present paper, we compare both methods in assessing neonatal respiratory status keeping two oxygenation indexes as standards.

Patients and methods

Neonates admitted to the NICU for respiratory distress were enrolled. Two neonatologists not attending the patients performed a lung scan, built a single frame database and rated the images with a standardized score. The same dataset was processed using the gray scale analysis implemented with textural features and machine learning analysis. Both the oxygenation ratio (PaO2/FiO2) and the alveolar arterial oxygen gradient (A-a) were kept as reference standards.

Results

Seventy-five neonates with different respiratory status were enrolled in the study and a dataset of 600 ultrasound frames was built. Visual assessment of respiratory status correlated significantly with PaO2/FiO2 (r = -0.55; p<0.0001) and the A-a (r = 0.59; p<0.0001) with a strong interobserver agreement (K = 0.91). A significant correlation was also found between both oxygenation indexes and the gray scale analysis of lung ultrasound scans using regions of interest corresponding to 50K (r = -0.42; p<0.002 for PaO2/FiO2; r = 0.46 p<0.001 for A-a) and 100K (r = -0.35 p<0.01 for PaO2/FiO2; r = 0.58 p<0.0001 for A-a) pixels regions of interest.

Conclusions

A semi quantitative estimate of the degree of neonatal respiratory distress was demonstrated both by a validated scoring system and by computer assisted analysis of the ultrasound scan. This data may help to implement point of care ultrasound diagnostics in the NICU.

Lung ultrasound as a monitoring tool in lung transplantation in rodents: a feasibility study

Background

Orthotopic lung transplantation in rats has been developed as a model to study organ dysfunction, but available tools for monitoring the graft function are limited. In this study, lung ultrasound (LUS) is proposed as a new non-invasive monitoring tool in awake rodents.

Methods

LUS was applied to native and graft lung of six rats after left orthotopic transplantation. Rats were monitored with LUS while awake, patterns identified, images evaluated with a scoring system, intra- and inter-rater agreement was assessed and examination times analyzed.

Results

A total of 78 clips were recorded. The median quality score of LUS was 3.66/4 for left hemithorax and 3.71/4 for native right side. The intra-rater agreement was 0.53 and 0.65 and the inter-rater agreement was 0.61 (P<0.01). Median time to complete the examination was 233.0 seconds (IQR 142) for both lungs, lowered from 254.0 seconds (IQR 129.5) (first trimester of study) to 205.5 seconds (IQR 88.5) (second trimester of the study). Significant findings on LUS were confirmed on pathological examination.

Conclusions

LUS in awake rodents without shaving has been shown to be both feasible and safe and the images collected were of good quality and comparable to those obtained in anesthetized rats without bristles.

Lung ultrasonography score versus chest X-ray score to predict surfactant administration in newborns with respiratory distress syndrome

OBJECTIVES

We aim to verify the diagnostic accuracy of a lung ultrasonography (LUS) score to early predict the need for surfactant therapy in newborns with respiratory distress syndrome (RDS), and to compare it with a chest X-ray score.

METHODS

In this prospective diagnostic accuracy study we included all newborns admitted for respiratory distress and initially treated with nasal CPAP. LUS was performed within 2 h from nasal CPAP positioning and in any case before surfactant administration. A chest X-ray was also performed. A LUS score and an X-ray score were used and compared. Ability of the scores to predict surfactant administration was evaluated through ROC analysis.

RESULTS

In our population of 56 newborns with mean gestational age of 31 weeks (SD 3) and mean birth weight of 1442 g (SD 520), LUS score showed higher AUC than X-ray score in early recognition of infants with respiratory distress syndrome requiring surfactant treatment (0.94; 95%CI, 0.89-0.98; P < 0.001 vs 0.80; 95%CI, 0.74-0.86; P < 0.001). It showed also higher sensitivity (86% vs 82%), higher specificity (88% vs 76%), better positive (83% vs 69%), and negative (91% vs 87%) predictive values.

CONCLUSIONS

LUS is a non-invasive, bedside and reproducible method that could improve the management of neonatal respiratory distress. It is accurate and reliable to early identify patients who will need treatment with surfactant allowing both an early treatment and a reduction of radiation exposure.

Point-of-care lung ultrasound in paediatric critical and emergency care

Ultrasound techniques have been developed since the past century and are becoming more useful in different areas of medical knowledge. More recently, lung ultrasound gained importance throughout artefacts analysis to help clinical evaluation at bedside and became subject of interest in the paediatric intensive care and emergency department settings for both procedural and diagnostic purposes. The normal pattern of lung ultrasound is defined by the presence of lung sliding associated with A-lines whereas B-lines may be representative of pathologic findings. This review focuses on some of the most common pulmonary conditions, their respective sonographic features and clinical implications in the emergency department and paediatric intensive care unit.

Effect of Needle Aspiration of Pneumothorax on Subsequent Chest Drain Insertion in Newborns: A Randomized Clinical Trial

IMPORTANCE

Treatment options for a symptomatic pneumothorax in newborns include needle aspiration (NA) and chest drain (CD) insertion. There is little consensus as to the preferred treatment, reflecting a lack of evidence from clinical trials.

OBJECTIVE

To investigate whether treating pneumothoraces diagnosed on chest radiography (CR) in newborns receiving respiratory support with NA results in fewer infants having CDs inserted within 6 hours of diagnosis.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was conducted from October 7, 2013, to December 21, 2016. The setting was 5 tertiary European neonatal intensive care units. Infants receiving respiratory support (endotracheal ventilation, continuous positive airway pressure, or supplemental oxygen >40%) who had a pneumothorax on CR that clinicians deemed needed treatment were eligible for inclusion.

INTERVENTIONS

Infants were randomly assigned (1:1) to drainage using NA or CD insertion, stratified by center and gestation at birth (<32 vs ≥32 weeks). Caregivers were not masked to group assignment. For NA, a needle was inserted between the ribs to aspirate air and was removed once air was no longer aspirated. A CD was inserted if clinicians deemed that the response was inadequate. For CD insertion, a drain was inserted between the ribs and was left in situ.

MAIN OUTCOMES AND MEASURES

The primary outcome was whether a CD was inserted on the side of the pneumothorax within 6 hours of diagnosis.

RESULTS

A total of 76 infants were randomly assigned, and 6 (4 assigned to NA and 2 to CD) were excluded because they met exclusion criteria at enrollment. Of the 70 remaining infants, 33 (16 male [48%]) were assigned to NA and 37 (22 male [59%]) to CD insertion. Their median (interquartile range [IQR]) gestational age was 31 (27-38) vs 31 (27-35) weeks, and their median (IQR) birth weight was 1385 (1110-3365) vs 1690 (1060-2025) g, respectively. Fewer infants assigned to NA had a CD inserted within 6 hours (55% [18 of 33] vs 100% [37 of 37]; relative risk, 0.55; 95% CI, 0.40-0.75) and during hospitalization (70% [23 of 33] vs 100% [37 of 37]; relative risk, 0.70, 95% CI, 0.56-0.87).

CONCLUSIONS AND RELEVANCE

Needle aspiration reduced the rate of CD insertion in symptomatic newborns with pneumothorax on CR. It should be used as the initial method of draining radiologically confirmed pneumothorax in symptomatic infants.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN65161530.

New directions in point-of-care ultrasound at the crossroads of paediatric emergency and critical care

PURPOSE OF REVIEW

The diagnostic capability, efficiency and versatility of point-of-care ultrasound (POCUS) have enabled its use in paediatric emergency medicine (PEM) and paediatric critical care (PICU). This review highlights the current applications of POCUS for the critically ill child across PEM and PICU to identify areas of progress and standardized practice and to elucidate areas for future research.

RECENT FINDINGS

POCUS technology continues to evolve and advance bedside clinical care for critically ill children, with ongoing research extending its use for an array of clinical scenarios, including respiratory distress, trauma and dehydration. Rapidly evolving and upcoming applications include diagnosis of pneumonia and acute chest syndrome, identification of intra-abdominal injury via contrast-enhancement, guidance of resuscitation, monitoring of increased intracranial pressure and procedural guidance.

SUMMARY

POCUS is an effective and burgeoning method for both rapid diagnostics and guidance for interventions and procedures. It has clinical application for a variety of conditions that span PEM and PICU settings. Formal POCUS training is needed to standardize and expand use of this valuable technology by PICU and PEM providers alike.

Ultrasound in neonatal lung disease

Lung diseases in neonates can be life-threatening condition and may result in respiratory failure and death. Chest X-ray is a traditional diagnostic technique that results in radiation exposure to patients. Lung ultrasound is a user-friendly imaging technique that has been increasingly used in clinical practice in recent years and presents the advantages of real-time imaging and without radiation. Here we review the sonographic appearances of common neonatal lung diseases and present demonstration of typical cases.

Lung ultrasound immediately after birth to describe normal neonatal transition: an observational study

OBJECTIVE

Lung ultrasound (LUS) has shown promise as a diagnostic tool for the evaluation of the newborn with respiratory distress. No study has described LUS during 'normal' transition. Our goal was to characterise the appearance of serial LUS in healthy newborns from the first minutes after birth until airway liquid clearance is achieved.

STUDY DESIGN

Prospective observational study.

SETTING

Single-centre tertiary perinatal centre in Australia.

PATIENTS

Of 115 infants born at ≥35 weeks gestational age, mean (SD) gestational age of 38^6/7 weeks±11 days, mean birth weight of 3380±555 g, 51 were delivered vaginally, 14 via caesarean section (CS) after labour and 50 infants via elective CS.

INTERVENTIONS

We obtained serial LUS videos via the right and left axillae at 1-10 min, 11-20 min and 1, 2, 4 and 24 hours after birth.

MAIN OUTCOME MEASURES

LUS videos were graded for aeration and liquid clearance according to a previously validated system.

RESULTS

We analysed 1168 LUS video recordings. As assessed by LUS, lung aeration and airway liquid clearance occurred quickly. All infants had an established pleural line at the first examination (median=2 (1-4) min). Only 14% of infants had substantial liquid retention at 10 min after birth. 49%, 78% and 100% of infants had completed airway liquid clearance at 2, 4 and 24 hours, respectively.

CONCLUSIONS

In healthy transitioning newborn infants, lung aeration and partial liquid clearance are achieved on the first minutes after birth with complete liquid clearance typically achieved within the first 4 hours of birth.

TRIAL REGISTRATION NUMBER

ANZCT 12615000380594.

Lung ultrasonography to diagnose pulmonary hemorrhage of the newborn

OBJECTIVES

This study was aimed to investigate the application of lung ultrasound for the diagnosis of pulmonary hemorrhage of the newborn (PHN).

METHODS

From July 2013 to June 2016, 157 neonates were enrolled in the study. They were divided into two groups: a study group of 57 neonates, who were diagnosed with PHN according to their medical history, clinical manifestations and chest X-ray findings, and a control group of 100 neonates with no lung disease. All subjects underwent bedside lung ultrasound in a quiet state in a supine, lateral or prone position, performed by a single expert physician. The ultrasound findings were compared between the two groups.

RESULTS

The lung ultrasound main findings associated with PHN included lung consolidation with air bronchograms with an incidence of 82.5%, a shred sign with an incidence of 91.2%, pleural effusion with an incidence of 84.2% (pleurocentesis confirmed the fluid was really bleeding), atelectasis with a incidence of 33.3%, pleural line abnormalities, as well as disappearing A-lines with an incidence of 100%, and 11.9% of these patients had the main manifestations of alveolar-interstitial syndrome (AIS). The shred sign exhibited a sensitivity of 91.2% and a specificity of 100% in diagnosing PHN.

CONCLUSIONS

Lung ultrasonography is useful and reliable for diagnosing PHN, which is suitable for routine application in the neonatal intensive care unit.

Lung ultrasound during the initiation of breathing in healthy term and late preterm infants immediately after birth, a prospective, observational study

INTRODUCTION

Lung ultrasound (LUS) has shown promise for evaluation of newborns with respiratory distress. However, no study has described the appearance of LUS during the initiation of breathing. We used LUS to describe the appearance of the lungs in healthy infants immediately after birth, starting with the infant's first breath, through the first 20min after birth.

METHODS

This was a single-center observational study enrolling neonates born at ≥35 weeks. We obtained LUS video recordings with the initiation of breathing. Recordings that captured one of the 1st four breaths after birth were included. We also obtained recordings at 1-10 and 11-20min after birth. Recordings were graded using a modified version of a previously published system, with additional grades to describe the appearance of the lungs prior to establishment of the pleural line.

RESULTS

We studied 63 infants, mean gestational age=39^1/7±2 days, mean weight=3473g±422, 33 infants were delivered vaginally and 30 via cesarean section. We captured the first breath after birth in 28 infants and within the first four breaths from the remaining 35 infants. The pleural line was established by a median of 4 breaths (3-6). At the 1-10min examination, all infants had an established pleural line and 89% demonstrated substantial liquid clearance. At the 11-20min examination, all infants had substantial liquid clearance.

CONCLUSION

Establishment of the pleural line, indicating lung aeration and substantial liquid clearance is achieved with the first few breaths after birth in term and near term infants.

Pediatric emergency medicine point-of-care ultrasound: summary of the evidence

The utility of point-of-care ultrasound is well supported by the medical literature. Consequently, pediatric emergency medicine providers have embraced this technology in everyday practice. Recently, the American Academy of Pediatrics published a policy statement endorsing the use of point-of-care ultrasound by pediatric emergency medicine providers.  To date, there is no standard guideline for the practice of point-of-care ultrasound for this specialty. This document serves as an initial step in the detailed "how to" and description of individual point-of-care ultrasound examinations.  Pediatric emergency medicine providers should refer to this paper as reference for published research, objectives for learners, and standardized reporting guidelines.